US3755795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrival detection and data transfer control system for data
Assignee: Information Storage Systems Inc
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Filing: 1971-08-23
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Granted: 1973-08-28
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Expires: 1991-08-23
Abstract
Abstract A disc pack type of random access memory apparatus is described which includes a system for detecting when a read/write head arrives in the proximity of an addressed track location on a disc under conditions assuring that data can be transferred between the head and the track without data being erroneously transferred to or from adjacent tracks. A differentiator is provided for determining from a head position signal the velocity of the head at a preselected distance from the center of the track. Upon a detector indicating that the head velocity at such preselected distance is equal to or below a value at which the head will not overshoot the track center beyond the range within which data can be safely transferred, the system will direct the start of data transfer between the head and the track even though the head has not yet settled at the track location.
Inventors
- 👤 F Sordello
- 👤 F Ruble
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:24
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/596; G11B5/59633; G11B5/59655; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
179 words
In a data memory apparatus of the type in which a data transfer device and a data storage device are positioned at various discrete locations relative to one another for the transfer of data therebetween, an arrival detection and data transfer control system for immediately initiating the transfer of data between said transfer device and said storage device upon said transfer device arriving within a selected proximity range around one of said locations under conditions by which said transfer device will remain within said proximity range for said transference of data, said system comprising means for determining the velocity of said data transfer device relative to said storage device at a preselected distance from said discrete location, and means responsive to a determination that said velocity is equal to or less than a predetermined upper velocity limit relative to said preselected distance over which limit said data transfer device will overshoot said discrete location and distance extending beyond the boundaries of said proximity range for directing the initiation of data transfer between said transfer device and said storage device.
Claim 2
Dependent Claim
179 words
In a data memory apparatus of the type in which a data transfer device and a data storage device are positioned at various discrete locations relative to one another for the transfer of data therebetween, an arrival detection and data transfer control system for immediately initiating the transfer of data between said transfer device and said storage device upon said transfer device arriving within a selected proximity range around one of said locations under conditions by which said transfer device will remain within said proximity range for said transference of data, said system comprising means for determining the velocity of said data transfer device relative to said storage device at a preselected distance from said discrete location, and means responsive to a determination that said velocity is equal to or less than a predetermined upper velocity limit relative to said preselected distance over which limit said data transfer device will overshoot said discrete location and distance extending beyond the boundaries of said proximity range for directing the initiation of data transfer between said transfer device and said storage device.
Claim 3
Dependent Claim
71 words
The data memory apparatus of claim 1 wherein means are included for generating a position signal representative at any given time of the position of said data transfer device with respect to said data storage device, and said means for determining the velocity of said data transfer device at said preselected distance includes differentiator means for determining the velocity of said signal at a state thereof representative of said preselected distance.
Claim 4
Dependent Claim
98 words
The data memory apparatus of claim 2 wherein said means for determining the velocity of said data transfer device relative to said storage device at a preselected distance from said discrete location includes a pair of level detectors, a first one of which is responsive to said positioning signal reaching said state representative of said preselected distance by generating a first output signal and a second one of which generates a second output signal upon the velocity of said position signal at said state being equal to or less than a level representative of said upper velocity limit.
Claim 5
Dependent Claim
73 words
The data memory apparatus of claim 3 wherein said position signal is a cyclical signal having slopes of opposite polarity at succeeding states thereof representative of said preselected distance from succeeding ones of said discrete locations, and each of said detectors is a bilateral level detector for providing detection of said velocities and said preselected distance irrespective of the polarity of the particular one of the states of said position signal representative thereof.
Claim 6
Dependent Claim
43 words
The data memory apparatus of claim 3 wherein said means responsive to a determination that said velocity is below a predetermined value relative to said preselected distance includes an AND gate to which the output signals of both of said detectors are directed.
Claim 7
Dependent Claim
80 words
The data memory apparatus of claim 5 wherein the output signal of said first level detector responsive to said position signal reaching the state thereof representative of said preselected distance is directed to means for forming a short time duration pulse in response to said level detector indicating said state, said pulse being directed to said AND gate for operating the same in conjunction with the output signal of said second level detector to produce a data transfer initiation signal.
Claim 8
Dependent Claim
73 words
The data memory apparatus of claim 6 wherein said position signal is a cyclical signal having slopes of opposite polarity at succeeding states thereof representative of said preselected distance from succeeding ones of said discrete locations, and each of said detectors is a bilateral level detector for providing detection of said velocities and said preselected distances irrespective of the polarity of the particular one of the states of said position signal representative thereof.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |